中文摘要：

试验采用营养液培养的方法，以玉米为试材，研究了不同供镉浓度（0、5、20和100μmol／L）和处理时间（12、2，4、48、96、168h）对植株体内钙调蛋白（CaM）含量及生物膜上的Ca^2＋＋ATPase活性的影响。结果表明，植株可溶性Ca^2＋含量在镉胁迫后较不加镉处理增加，镉处理在叶和根中分别在48和24h后达最高，然后随镉处理浓度和处理时间的增加逐步下降；同时镉诱导了植株CaM的合成，其含量随镉处理浓度和处理时间增加逐步增加，但20μmol／L和100μmol／L镉处理在168h后有所下降；与不加镉处理相比，镉胁迫导致植株生物膜上的Ca^2＋-ATPase活性迅速升高，但随镉处理浓度提高和时间延长，镉胁迫植株的Ca^2＋-ATPase活性在48h（质膜、液泡膜和内质网膜）和24h（线粒体膜）后逐步降低。各膜上的Ca^2＋-ATPase活性依次为质膜〉液泡膜〉内质网膜〉线粒体膜，且同一微囊膜，根中的活性大于叶中。

英文摘要：

A hydroponics culture experiment was conducted to examine the effects of cadmium （Cd） stress on calmodulin （CAM） content and Ca2^＋-ATPase activities in maize （Zea mays） plant. Maize seedlings were treated with 0, 5, 20, and 100μmol/L Cd for periods of 12 to 168 h. Results showed that the content of soluble Ca^2＋ in plant were increased by cadmium stress. The highest levels of soluble Ca^2＋ in leaves and roots were found in the plants with 48 h and 24 h exposure to Cd respectively. CaM content in plants was enhanced with increasing Cd concentrations and prolonged Cd treatment. However, CaM content in plants began to decrease after 168 h treatments of 20μmol/L and 100μmol/L Cd. The Ca^2＋ -ATPase activities of Cd stressed plants were higher than that without Cd addition, but they decreased gradually with higher concentrations of Cd and extended Cd treatment after 48 h （plasma, tonoplast and endoplasmic reticulum membrane） and 24 h （mitochondrial membrane）. The decrease of Ca2^＋ -ATPase activities in cell membrane systems showed the following pattern： plasma membrane 〉 tonoplast membrane 〉 endoplasmic reticulum membrane 〉 mitochondrial membrane. The Ca^2＋ -ATPase activities of the same microsomal were higher in root than in leaf.